Splenectomy

One option to improve the platelet counts in patients who are not candidates for transplant is splenectomy, a procedure where the spleen is removed. This organ functions as a "filter" for removing old and abnormal red cells and is a storage site for platelets and white blood cells. The spleen has also an important role in the immune system, by filtering and removing foreign molecules and infectious agents, producing antibodies and providing a site for lymphocyte immune function. In WAS patients the spleen is thought to remove and/or entrap abnormal platelets which has an important role in causing the lower platelet counts and their reduced size.

In the study by Mullen et al the incidence of fatal sepsis in patients who were on prophylactic antibiotics was 1.2 out of 100 patients per year (which is five times more than the rate for a splenectomized child who does not have WAS).

Preliminary analysis of a recent survey of 182 patients with XLT2 showed that the incidence of serious infections to be 33%(fatal and non fatal sepsis) in the absence of antibiotic prophylaxis. There was a trend towards less severe infectious episodes after splenectomy in patients with antibiotic prophylaxis (16% vs. 33%)

However, another study of 15 patients suggested that there was a minimal incidence of sepsis noted when IVIG was given14 along with antibiotic prophylaxis. Most physicians seem to advocate the use of monthly IVIG after splenectomy whereas others do not. Some patients who were on antibiotic prophylaxis have developed sepsis with bacteria that were resistant to the antibiotic. In these patients, the prophylactic antibiotics may have reduced the rapidity of the onset of sepsis. IVIG may be given to prevent infections with bacteria that are resistant to antibiotics and for those few cases where the sepsis is caused by bacteria sensitive to antibiotics.

WASP

Positive

Negative

P

Stem cell transplantation, n

3

12

—

Mean age, y

12.4

12.8

.017

Age range, y

0.25-19

0.5-14

—

Alive, n

3

11

—

Dead, n

0

1

—

Splenectomy, n

5

5

—

Mean age at present, y

17.0

5.0

.017

Range, y

0-59

1.0-8.2

—

Mean age at splenectomy, y

8.8

6.0

—

Range, y

2-23

0.3-9

—

Alive, n

5

2

—

Dead, n

0

3

—

Good response, n (%)*

2 (40)

3 (60)

—

Partial response, n (%)*

3 (60)

2 (40)

—

No response, n

0

0

—

Pneumococcal sepsis/meningitis after splenectomy, n

2

3

—

High-dose IVIG, n

13

11

—

Good response, n*

0

0

—

Transient response, n (%)

4 (31)

2 (18)

—

No response, n (%)

9 (69)

9 (82)

—

Steroids, n

15

11

—

Good response, n*

0

0

—

Transient response, n (%)

8 (53)

2 (18)

—

No response, n (%)

7 (47)

9 (82)

—

Table 8..WASP expression and response to therapy

WASP

Positive

Negative

P

Stem cell transplantation, n

3

12

—

Mean age, y

12.4

12.8

.017

Age range, y

0.25-19

0.5-14

—

Alive, n

3

11

—

Dead, n

0

1

—

Splenectomy, n

5

5

—

Mean age at present, y

17.0

5.0

.017

Range, y

0-59

1.0-8.2

—

Mean age at splenectomy, y

8.8

6.0

—

Range, y

2-23

0.3-9

—

Alive, n

5

2

—

Dead, n

0

3

—

Good response, n (%)*

2 (40)

3 (60)

—

Partial response, n (%)*

3 (60)

2 (40)

—

No response, n

0

0

—

Pneumococcal sepsis/meningitis after splenectomy, n

2

3

—

High-dose IVIG, n

13

11

—

Good response, n*

0

0

—

Transient response, n (%)

4 (31)

2 (18)

—

No response, n (%)

9 (69)

9 (82)

—

Steroids, n

15

11

—

Good response, n*

0

0

—

Transient response, n (%)

8 (53)

2 (18)

—

No response, n (%)

7 (47)

9 (82)

—

WASP-positive numbers represent WASP detectable by Western blot. WASP-negative numbers represent WASP found absent or truncated by Western blot. — indicates not applicable.

5. A French study16 showed that patients who had a high level of IgM prior to splenectomy seemed to have a higher rate of development of Autoimmune Hemolytic Anemia. This has not been confirmed in other studies, but it seems prudent to measure IgM levels prior to splenectomy and if it is elevated, discuss the decision further with experts.

Once considered routine in the management of patients with WAS12 who were not candidates for transplant, splenectomy is losing favor in the treatment of uncomplicated thrombocytopenia in WAS. This is due the increased incidence of serious sepsis noticed in these patients. It could also be due to the significant advances in the field of transplants. Patients with Classic WAS are transplanted. Patients who require more platelet support or develop ITP may be guided onto the transplant pathway as opposed to the splenectomy pathway which addresses only one of the issues faced by these patients. One other factor could be that patients with XLT have lesser number of fatal hemorrhages as compared to patients with Classic WAS. These children are able to live a fairly "normal" life with lower platelet counts and some experts feel that the risk of serious sepsis is more than the risk of a serious bleed. Until experts can concur on what is best for the patients, parents are left, once again, to make these difficult and life altering decisions on behalf of their children.

Post Splenectomy Care

Patients without a spleen are at risk of overwhelming sepsis. In addition to being vulnerable to infections with bacteria, particularly the encapsulated organisms such as Pneumococcus and Meningococcus, these patients need to be aware that they are more vulnerable to infection after dog bites, tick bites and to malaria. Receiving vaccines, taking antibiotics and IVIG does not protect always protect a patient from sepsis and there must be a high degree of vigilance that is maintained. If these patient develop a fever of greater than 101o F or 38.3o C, they should be seen at once in the ER to have cultures done and to have antibiotics started. Splenectomized patients may not develop a fever with sepsis and it is important that if they are feeling unwell and uncomfortable, they should be seen at once as this could be sepsis.

Life long antibiotic prophylaxis is needed with medications such as Pen V twice a day(it may be given once a day if compliance is a problem) or Amoxiciilin once a day or with erythromycin once a day in patients who with penicillin allergies.

All patients should carry an emergency card to alert emergency health personnel about the risk of overwhelming infection. Patients should wear a medical alert bracelet or pendant.

All patient records should be clearly labeled to indicate the risk of infection.

A clear record of all vaccinations and boosters given should be recorded.

Consider recommending patient take a full therapeutic dose of antibiotics if they develop infection symptoms such as fever, malaise, shivering etc. and seek medical advice immediately.

Allowing patients a reserve supply of antibiotics at home or on holiday may also seem appropriate.

All patients with severe WAS should continue on their regular regimen of monthly IVIG after a splenectomy. There is no consensus on whether IVIg is to be given in patients with XLT who have undergone splenectomy. Some physicians advocate this as there have been studies that suggested a decreased incidence of sepsis when IVIG was administered14 along with prophylactic antibiotics. This could be due to the fact that the IVIG could protect the patient against infection with antibioitc resistant organisms or slow the rate of progression of infection.